Medical disclaimer: Eczema and psoriasis are diagnosed medical conditions. This article is for educational purposes only and does not constitute medical advice or replace treatment from a licensed dermatologist. If you have a diagnosed condition, work with your healthcare provider before changing your skincare routine.

Most eczema and psoriasis skincare advice stops at "use a fragrance-free moisturizer and avoid triggers." That's not wrong — but it's incomplete. The past decade of dermatological research has reframed both conditions through the lens of the skin microbiome: a disrupted microbial ecosystem that perpetuates inflammation, impairs barrier function, and creates a cycle that generic moisturizers alone can't break. Here's what the evidence actually shows, and how to build a protocol around it.

The Shared Root: Microbiome Disruption & Barrier Failure

Eczema (Atopic Dermatitis)

Atopic dermatitis is characterized by a loss of Staphylococcus epidermidis diversity and an overgrowth of Staphylococcus aureus, which produces toxins that trigger IgE-mediated inflammation and further damage the skin barrier. Grice & Segre (2011), Nature Reviews Microbiology, PMID 21407241. Simultaneously, mutations in the filaggrin gene (FLG) impair the skin's ability to produce natural moisturizing factor (NMF), leading to transepidermal water loss (TEWL) and a permeable barrier that allows allergens and irritants to penetrate.

Evidence tier: TIER 1 — The microbiome-barrier-inflammation axis in atopic dermatitis is confirmed by multiple peer-reviewed studies and is now the basis for next-generation treatments including microbiome-targeted biologics.

Psoriasis

Psoriasis is a T-cell-mediated autoimmune condition, but the skin microbiome plays a modulatory role. Psoriatic skin shows reduced microbial diversity and altered Firmicutes/Bacteroidetes ratios compared to healthy skin. Alekseyenko et al. (2013), Microbiome, PMID 24135510. Barrier dysfunction in psoriasis is secondary to the inflammatory cascade rather than primary (as in eczema), but the result — a compromised, reactive skin surface — requires similar management strategies.

Evidence tier: TIER 2 — Early clinical research suggests microbiome modulation as a therapeutic target in psoriasis; this is an active area of research.

What This Means for Your Skincare Protocol

The microbiome framing changes the protocol in three important ways:

1. Avoid ingredients that disrupt microbial diversity — harsh surfactants, high-concentration alcohols, and broad-spectrum antimicrobials can worsen dysbiosis
2. Prioritize barrier-repair ingredients that support the microbiome — ceramides, fatty acids, and postbiotics create an environment where beneficial bacteria can thrive
3. Use anti-inflammatory ingredients that don't suppress the entire immune response — targeted botanicals (centella asiatica, colloidal oatmeal, PEA) rather than broad immunosuppressants

The Ingredient Hierarchy

Ceramides

Ceramides make up approximately 50% of the lipid content of the stratum corneum. In eczema, ceramide levels are significantly reduced. Topical ceramide-containing moisturizers have been shown to reduce TEWL and improve barrier function. Chamlin et al. (2002), Journal of the American Academy of Dermatology, PMID 12522378. Look for products containing ceramide NP, AP, and EOP together with cholesterol and free fatty acids — the ratio matters.

Colloidal Oatmeal

FDA-approved as a skin protectant for eczema. Avenanthramides in oatmeal inhibit NF-κB signaling and reduce histamine-induced itch. Fowler et al. (2012), Journal of Drugs in Dermatology, PMID 22481014. Use in cleansers, bath soaks, and moisturizers.

Centella Asiatica (CICA)

Madecassoside suppresses NF-κB and reduces pro-inflammatory cytokines without broad immunosuppression. Well-tolerated in eczema-prone skin. See: The CICA Protocol.

PEA (Palmitoylethanolamide)

An endocannabinoid-adjacent lipid mediator with anti-inflammatory and anti-itch properties. Eberlein et al. (2008), Journal of Dermatological Treatment, PMID 18608837: PEA-containing cream significantly reduced itch and improved skin condition in atopic dermatitis patients. See: PEA for Skin: The Anti-Inflammatory Going Viral for Eczema.

Tallow (Grass-Fed)

Grass-fed tallow contains a fatty acid profile (oleic acid, palmitic acid, stearic acid) that closely mirrors human sebum. For eczema-prone skin, tallow provides occlusion and fatty acid replenishment without synthetic emulsifiers that can disrupt the microbiome. The fragrance-free formulations are the appropriate choice. See: Beef Tallow for Eczema: Confirm or Bust and the full science guide at Grass-Fed Tallow Skincare: The Ancestral Beauty Trend Backed by Science.

The Protocol: Flare vs. Maintenance

Psoriasis-Specific Considerations

Psoriasis plaques are thickened, scaly, and require different management than eczema. Salicylic acid (2–3%) is an effective keratolytic for scale removal and is well-tolerated in psoriasis. Coal tar preparations have the longest evidence base for psoriasis management but are cosmetically challenging. For scalp psoriasis, medicated shampoos (salicylic acid, coal tar, ketoconazole) are first-line OTC options. Systemic psoriasis requires dermatologist management — this protocol addresses the skin surface only.

What Doesn't Work (And Why)

• Essential oils — many are potent allergens and contact sensitizers; avoid in eczema-prone skin
• "Natural" soaps with fragrance — fragrance is the #1 contact allergen in skincare
• Coconut oil as a primary moisturizer — high lauric acid content is antimicrobial and may worsen dysbiosis; also comedogenic
• Bleach baths without medical supervision — evidence exists for dilute bleach baths in eczema, but concentration matters; DIY bleach baths can cause chemical burns

Related Reading

• The CICA Protocol: Centella Asiatica for Sensitive Skin
• PEA for Skin: The Anti-Inflammatory Going Viral for Eczema
• Skin SOS: The Barrier Bible
• Beef Tallow for Eczema: Confirm or Bust
• Grass-Fed Tallow Skincare: The Ancestral Beauty Trend Backed by Science
• The Complete Veracil Skincare System — All Protocols

Commercial disclosure: Veracil sells skincare products including some referenced in this article. All product recommendations are based on ingredient compatibility with the protocol described above.

Shop This

• Fragrance Free Tallow + Honey Cream for Sensitive Skin — The ideal occlusive for eczema-prone skin: fragrance-free, fatty acid-rich, and formulated for reactive skin. Apply within 3 minutes of bathing for maximum barrier sealing.
• Organic Whipped Tallow Balm — Pure grass-fed tallow with a fatty acid profile that mirrors human sebum. A clean, minimal-ingredient occlusive for severely compromised barriers.
• Soft & Gentle Buttermilk Tallow & Goat Milk Soap Bar — Fragrance-Free — A fragrance-free, gentle cleansing bar for eczema and sensitive skin. Tallow and goat milk provide lipid replenishment while cleansing.
• SKIN1004 Madagascar Centella Ampoule — High-potency CICA ampoule for anti-inflammatory support between flares. Apply before your occlusive layer.
• ANUA Heartleaf 77% Soothing Toner — A calming, hydrating toner for the maintenance phase. Heartleaf (houttuynia cordata) has documented anti-inflammatory properties for reactive skin.
• Blue Beauty Cream Soothing Tallow Face Cream — A soothing tallow face cream formulated for reactive and sensitive skin. Blue tansy provides additional anti-inflammatory support.